Field of the Invention
The invention relates to an inductor-type converter having an inductor arranged between a first and a second node in the diagonal of an H-bridge topology that is operated with a supply voltage. The invention further relates to methods of operating the novel inductor-type converter.
Inductor-type converters make use of the effect that when a DC voltage is applied to an inductor, the current flowing through the latter rises with time linearly to a first approximation. If the voltage across the inductor is pulsed a specific output voltage is produced. Varying the duty ratio enables variation of the output voltage for a predetermined input voltage.
Step-up regulators, in which the output voltage may be greater than the input voltage, and step-down regulators, in which the output voltage may be less than the input voltage, are known in the pertinent art.
Such step-up and step-down regulators are disclosed in Stengl/Tihanyi "Leistungs-MOS-FET-Praxis" [Practical Power MOS-FETs], Pflaum Verlag Munich, 1992, pp. 176-77. A dedicated inductor is in each case necessary both for a step-up regulator and for a step-down regulator.
U.S. Pat. No. 5,552,694 discloses an inductor-type converter having an inductor which can be operated either as a step-up converter or as a step-down converter. That converter outputs an output voltage which is either greater or smaller than the input voltage.